The Research On Admission Control And Load Balancing Algorithm In Td-Lte System

Long term evolution (LTE) that is proposed by3GPP is the3G network evolution direction. In order to meet the various needs of the traffic, LTE should provide higher transmission data rates, greater network capacity and smaller delay. Radio resource management (RRM) play an important role in the LTE network capacity and performance, this paper focus on call admission control and load balancing which are the main contents of RRM.In this paper, we have an in-depth study of call admission algorithm in LTE system. In order to reduce the new call blocking probability (NCBP) and handover call dropping probability (HCDP) while guaranteeing the QoS of the LTE network, a novel bandwidth adaptation admission control algorithm is proposed. In this scheme, admission decision is made based on the traffic QoS, time-varying capacity of the system and priority of the connection request. The concepts of QoS satisfaction and bandwidth preemption value (BPV) are proposed. The basic idea is that connection request with high BPV can preempt the bandwidth of the existing connections with low BPV. When admission algorithm is executed, the connection request is accepted if it passes through capacity judgment and QoS satisfaction judgment. Thus, the success rate of accessing the network of connection request with high traffic priority is higher than that of connection request with low traffic priority. Furthermore, the analysis and simulation results show that the proposed algorithm reduces the NCBP and HCDP effectively while guaranteeing QoS satisfaction.In this paper we pay much attention on load balancing. Load balancing is an important part of SON network. The goal of load balancing is transfer part of load of overload cell to the low load adjacent cell, so as to enhance the network performance. Based on a lot of reading literatures, a load balancing and GBR user joint optimization is proposed, the algorithm takes into account the Load Balancing Index (LBI) and the average delay of GBR users. The algorithm is divided into two parts. One is load balancing and another is admission control. The effect of load balancing is to make sure that the network load is more uniform and the LBI is larger. The effect of admission control is to avoid switching excessive GBR users to the neighboring area that can result in the increase of the average delay. A new resource estimation method that is dependent on the actual calculation of SINR is utilized in load balancing algorithm. The analysis and simulation results show that the joint algorithm not only achieves load balancing, but also ensure the average delay of GBR users.